Each subpart: 3 Marks
a) Let M.P. be Rs x
Then,
⇒810=x+8% of x=x+8100x
⇒810=108100x
⇒810×100108=x
⇒x=750
Amount to be paid if sales tax is reduced to 6% = Rs750+6% of Rs 750
=Rs750+Rs 6100×750=Rs 795
b)
Let M.P. be Rs x
Then, 13407 = x + 9% of
⇒13407=x+9100x
⇒13407=109100x
⇒13407×100109=x
⇒ x = 12300
Hence, marked price is Rs 12300
Sales tax = 13% of Rs 12300
=Rs 13100×12300=Rs 1599
Amount to be paid = Rs 12300 + Rs 1599 = Rs 13899
Extra amount to be paid = Rs 13899 - Rs 13407 = Rs 492